1 /* 2 * Copyright (c) 1983, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifndef lint 35 static char copyright[] = 36 "@(#) Copyright (c) 1983, 1993\n\ 37 The Regents of the University of California. All rights reserved.\n"; 38 #endif /* not lint */ 39 40 #ifndef lint 41 /* 42 static char sccsid[] = "@(#)fingerd.c 8.1 (Berkeley) 6/4/93"; 43 */ 44 static const char rcsid[] = 45 "$Id$"; 46 #endif /* not lint */ 47 48 #include <sys/types.h> 49 #include <sys/socket.h> 50 #include <netinet/in.h> 51 #include <netinet/tcp.h> 52 #include <arpa/inet.h> 53 #include <errno.h> 54 55 #include <unistd.h> 56 #include <syslog.h> 57 #include <netdb.h> 58 #include <stdio.h> 59 #include <stdlib.h> 60 #include <strings.h> 61 #include "pathnames.h" 62 63 void logerr __P((const char *, ...)); 64 65 int 66 main(argc, argv) 67 int argc; 68 char *argv[]; 69 { 70 register FILE *fp; 71 register int ch; 72 register char *lp; 73 struct hostent *hp; 74 struct sockaddr_in sin; 75 int p[2], logging, secure, sval; 76 #define ENTRIES 50 77 char **ap, *av[ENTRIES + 1], **comp, line[1024], *prog; 78 79 prog = _PATH_FINGER; 80 logging = secure = 0; 81 openlog("fingerd", LOG_PID | LOG_CONS, LOG_DAEMON); 82 opterr = 0; 83 while ((ch = getopt(argc, argv, "slp:")) != EOF) 84 switch (ch) { 85 case 'l': 86 logging = 1; 87 break; 88 case 'p': 89 prog = optarg; 90 break; 91 case 's': 92 secure = 1; 93 break; 94 case '?': 95 default: 96 logerr("illegal option -- %c", ch); 97 } 98 99 if (logging) { 100 sval = sizeof(sin); 101 if (getpeername(0, (struct sockaddr *)&sin, &sval) < 0) 102 logerr("getpeername: %s", strerror(errno)); 103 if (hp = gethostbyaddr((char *)&sin.sin_addr.s_addr, 104 sizeof(sin.sin_addr.s_addr), AF_INET)) 105 lp = hp->h_name; 106 else 107 lp = inet_ntoa(sin.sin_addr); 108 syslog(LOG_NOTICE, "query from %s", lp); 109 } 110 111 /* 112 * Enable server-side Transaction TCP. 113 */ 114 { 115 int one = 1; 116 if (setsockopt(STDOUT_FILENO, IPPROTO_TCP, TCP_NOPUSH, &one, 117 sizeof one) < 0) { 118 logerr("setsockopt(TCP_NOPUSH) failed: %m"); 119 } 120 } 121 122 if (!fgets(line, sizeof(line), stdin)) 123 exit(1); 124 125 comp = &av[1]; 126 av[2] = "--"; 127 for (lp = line, ap = &av[3];;) { 128 *ap = strtok(lp, " \t\r\n"); 129 if (!*ap) { 130 if (secure && ap == &av[3]) { 131 puts("must provide username\r\n"); 132 exit(1); 133 } 134 break; 135 } 136 if (secure && strchr(*ap, '@')) { 137 puts("forwarding service denied\r\n"); 138 exit(1); 139 } 140 141 /* RFC742: "/[Ww]" == "-l" */ 142 if ((*ap)[0] == '/' && ((*ap)[1] == 'W' || (*ap)[1] == 'w')) { 143 av[1] = "-l"; 144 comp = &av[0]; 145 } 146 else if (++ap == av + ENTRIES) 147 break; 148 lp = NULL; 149 } 150 151 if (lp = strrchr(prog, '/')) 152 *comp = ++lp; 153 else 154 *comp = prog; 155 if (pipe(p) < 0) 156 logerr("pipe: %s", strerror(errno)); 157 158 switch(vfork()) { 159 case 0: 160 (void)close(p[0]); 161 if (p[1] != 1) { 162 (void)dup2(p[1], 1); 163 (void)close(p[1]); 164 } 165 execv(prog, comp); 166 logerr("execv: %s: %s", prog, strerror(errno)); 167 _exit(1); 168 case -1: 169 logerr("fork: %s", strerror(errno)); 170 } 171 (void)close(p[1]); 172 if (!(fp = fdopen(p[0], "r"))) 173 logerr("fdopen: %s", strerror(errno)); 174 while ((ch = getc(fp)) != EOF) { 175 if (ch == '\n') 176 putchar('\r'); 177 putchar(ch); 178 } 179 exit(0); 180 } 181 182 #if __STDC__ 183 #include <stdarg.h> 184 #else 185 #include <varargs.h> 186 #endif 187 188 void 189 #if __STDC__ 190 logerr(const char *fmt, ...) 191 #else 192 logerr(fmt, va_alist) 193 char *fmt; 194 va_dcl 195 #endif 196 { 197 va_list ap; 198 #if __STDC__ 199 va_start(ap, fmt); 200 #else 201 va_start(ap); 202 #endif 203 (void)vsyslog(LOG_ERR, fmt, ap); 204 va_end(ap); 205 exit(1); 206 /* NOTREACHED */ 207 } 208